Baby car seats (group 0+) are usually the first car seat you'll buy. They are smaller and lighter than the car seats you'll use as your child gets older. They are also rearward facing – so your baby will be travelling with his or her back to you when you're driving. Research shows it's safest for babies to travel in a rear-facing seat for as long as possible.
Group 0+ car seats will last your baby from birth until he or she is around 12 to 15 months old, with a maximum weight of 13kg for most baby car seats.
Some group 0+ baby car seats are designed so that you can also attach them to a pushchair chassis to form a travel system. This means that you can take your baby from car to pushchair without having to disturb them too much. Avoid keeping babies, particularly very young ones, in car seats any longer than absolutely necessary and car seats should not be used for sleeping inside the house.